ML20207F377
| ML20207F377 | |
| Person / Time | |
|---|---|
| Site: | Fort Saint Vrain  |
| Issue date: | 07/15/1986 |
| From: | Robert Williams PUBLIC SERVICE CO. OF COLORADO |
| To: | Berkow H Office of Nuclear Reactor Regulation |
| References | |
| P-86462, TAC-54373, NUDOCS 8607220528 | |
| Download: ML20207F377 (28) | |
Text
-
OPublic Service-Company of Colorado 2420 W. 26th Ave., Suite 100D. Denver, Colorado 80211 July 15, 1986 Fort St. Vrain Unit No. 1 P-86462 Director of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington D.C.
20555 Attn: Mr. H.N. Berkow, Director Standardization and Special Projects Directorate Docket No. 50-267
SUBJECT:
Appendix R Evaluation
REFERENCES:
- 1) PSC Letter, Walker to Berkow, dated December 20, 1985 (P-85488)
- 2) PSC Letter, Walker to Berkow, dated March 14, 1986 (P-86209)
- 3) PSC Letter, Walker to Berkow, dated April 4,1986 (P-86266)
- 4) PSC Letter, Lee to Johnson, dated August 17, 1984 (P-84281)
- 5) PSC Letter, Lee to Johnson, dated April 1, 1985 (P-85113)
Dear Mr. Berkow:
PSC committed (References 2 & 3) to provide the NRC with an evaluation of the local manual operations required for a fire in each area, and assessment of the adequacy of present staffing levels to accomplish fire protection shutdown in accordance with the Fort St.
Vrain evaluation criteria.
This submittal is based on recent ggb 8607220528 e60715 PDR ADOCK 05000267 F
/
P-86462 July 15, 1986 s
information concerning changes to staffing level at Fort St. Vrain.
The addition of another reactor operator on each shift allows four personnel to be available for shutdown operations, independent of the fire brigade, and additionally allows the Shift Supervisor to be available in the Control Room so that security and emergency plan requirements will still be met.
It should be noted that this information supersedes responses 1.b and 13 of Reference 1.
In addition, we have included 20 copies of a correction to a reference made on page 3-7 in Report No. 4 (Reference No. 5) of the Fort St. Vrain Appendix R Evaluation.
Please incorporate this into your copies of the report.
If you have any questions please contact Mr. M.H. Holmes at (303) 480-6960.
Very truly yours, 2
R. O, Williams, Vice President Nuclear Operations R0W/FT:pa Attachment
Attachm:nt tt P-86462 ASSESSMENT OF STAFFING FOR LOCAL MANUAL OPERATIONS - FIRE PROTECTION SHUTDOWN The response to NRC Question No. 12.b in PSC's December 20, 1985 letter (P-85488) provided a general summary of required operator actions and estimated times for performing these. The response to Question No. 13 identified the number of personnel available on-shift, including the number available to perform post-fire shutdown operations. This evaluation supersedes the information contained in those responses, and provides an assessment demonstrating the adequacy of staffing levels to perform post-fire shutdown manual operations.
This evaluation also includes a summary of the specific actions that could potentially be needed to be performed for a fire in each area.
The shutdown analyses that have been performed for Fort St. Vrain and described in Report Nos. I thru 4 identified the sum total of all equipment that could potentially require local operator action following a fire. These components are summarized in the updated Table 3.1 of Report No.
1 in the areas of Valves - Manual Only, Valves - Operated Locally, and Instrumentation. Since a particular corrective action may only be required if a certain spurious operation occurs, and local control would be required only if control from the Control Room is not available, only a subset of the equipment listed in the above categories may require local manual operations depending on the fire area.
To assess the required actions for a given fire area, numerous circuit analyses were performed to determine areas where spurious operations could occur, or where loss of function from the Control Room may also occur. This resulted in a determination of equipment requiring local operation, given a fire in each area. The principal areas of concern are the Reactor Building and Turbine Building due to the extent of equipment, power and control that could be affected.
Additionally, a fire in the Service Water Pump House results in significant manual operations to establish an alternate means of service water cooling.
The equipment requiring local manual operations or observations are listed in Table 1 for these areas.
Attachment to P-86462 Other plant areas, in addition to the Reactor Building, the Turbine Building, and Service Water Pump House, require minimal or no local manual
- action, e.g.,
the Auxiliary Boiler Room, Cooling Tower, Circulating Water Pump Pit, ACM Diesel / control
- areas, Diesel Generator Room, Fire Water Pump House, etc. Due to the minimal actions required for fires in these areas, they have not been included in the Table 1 listing.
Reasonable estimates were established, based on judgment of personnel with plant operating experience, for average times to perform certain types of actions.
These estimates were established to provide a uniform assessment of minimum time _ required for performing a set of operator actions. Times for performing operator actions are average times, that include moving from valve to valve. These averages are believed to be reasonable since most of the valves are in the same immediate vicinity, such as the set of valves associated with the circulator brake and seal, circulator water drive, etc. Once the operator reaches a desired location, several valves in close proximity can be operated, with the time per valve much less than the averages shown.
1.
Access to an area, or passage between fire areas 10 minutes 2.
Valve position verification 1/2 minute per item in Turbine Building (TB) and 1 minute per item in the Reactor Building (RB) 3.
Valve repositioning, operation of a transfer switch, reading of an instrument 1 minute per item in the TB, and areas outside the RB and TB, and 2 minutes per item in the RB 4.
Access to an area affected by fire 45 minutes delay, and then 10 minute access time.
Attachm:nt to P-86462 Although specific NRC criteria have not been established on minimum allowable time prior to re-entry into a building, some guidance is available in a letter dated April 20, 1982 from the NRC to Mr. S. A.
Bernsen of Bechtel Power, a copy of which is attached.
In that letter the NRC Staff was responding to questions related to returning to the Control Room after a fire. On pages 2 and 3 of that letter, the Staff identified four steps that would have to be satisfied before considering that control from the Control Room is available.
To accomplish these steps, operator access to the Control Room is required prior to the 1-hour period in order to assess status and operability of instrumentation and controls, such that the necessary assessment of availability and turn-over in controls is completed within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> of fire initiation.
To allow time for damage assessment and turn-over actions, operators need to re-enter the Control Room about 45 minutes after fire initiation.
It should be noted that this situation is addressing the relatively confined space of the Control Room, and is not addressing re-entry into a large open space such as the Fort St. Vrain Reactor or Turbine Buildings.
In these large open spaces of the Reactor and Turbine Buildings, it is not feasible that entry into these buildings is prevented for a 1-hour time period. Operations personnel should be able to perform limited corrective actions, and assess extent of damage. Access would likely only be rettricted to the specific locality of where the fire occurred within the Turbine Building or Reactor Building.
Nonetheless, the assessment performed for Fort St. Vrain conservatively assumed that no operator actions would take place within the building where the fire occurs for the first 45 minutes, and that re-entry may start to take place for operations personnel at the 45-minute point.
The times that were established also add another 10 minutes for operators to get from the assembly location to the specific location where the first local manual operations must take place. Thus, this assessment incorporates a time of closer to 50 minutes to be at the point where operators are starting to enter the building where the fire occurred to initiate the local manual operations.
Attachment to P-86462 It should be noted that Specific Criterion III.I, from the Reference 4 letter concerning the Fort St. Vrain Appendix R acceptance criteria, states that the performance of local manual operations to water-filled mechanical components in the fire area, rcom, or zone shall be considered possible within one hour after the start of the fire. The exemption requests submitted in Report No. 4 (Reference 5) justify that a fire in the Reactor or Turbine Buildings would not encompass the entire building; modifications were proposed such that separation of components by 30 feet or greater is achieved (as described in exemption requests). Thus, the zone of influence of a postulated fire is considered to be something less than these separation distances.
The set of actions per fire area for each Train was divided into groups based on equipment location (See Figs. 2.1 and 2.2 attached) so that these could be subdivided among the available operators.
Refer to the attached Table 1 for the equipment requiring operations / observation by the fire area and shutdown train. A review of this table illustrates that of the set of equipment and manual actions that may be required for any area, and thus must be included in the shutdown model, a much smaller subset would be required depending on the location of the fire.
Based on the type of actions in each group, minimum times were established for each group as summarized in the attached Table 2.
The minimum on-shift crew required by Technical specifications (Table 7.1-1) consists of the following personnel:
1 Shift Supervisor 1
Senior Reactor Operator 2
Reactor Operators 1
Equipment Operator 1
Auxiliary Tender
=
Attachment to P-86462
' This was accomplished by having 2 Equipment Operators, one of whom held valid Reactor Operator's License, and 1 Reactor Operator as allowed by note (b) to the Technical Specification table.
The normal scheduled on-shift crew now consists of the following personnel:
1 Shift Supervisor 1
Senior Reactor Operator 2
Reactor Operators 2
Equipment Operators (*1 on turbine side, 1 on reactor side) 2
- Auxiliary Tenders 1
- Lead Security Officer 1
- Health Physics Technician
- Assigned to Fire Brigade This includes a recent change to require an additional Reactor Operator on each shift.
Controls on staffing levels have been accepted at other plants for Appendix R shutdown actions and the fire brigade. With five of the ten on-shift personnel dedicated to the fire brigade, the remaining five personnel are available for shutdown activities; however, one of the personnel (the Shift Supervisor) is required to remain in the Control Room by the Emergency Plan, without performing operator actions. This leaves four personnel to effect the post-fire manual actions.
Of these individuals, one operator must remain in the Control Room to coordinate activities, monitor available instrumentation, and control equipment from the Control Room once required local operations and valve alignments are completed.
The remaining three personnel may perform the local manual actions reflected in the Groupings of Table 1.
The attached Table 3 illustrates the shutdown scenarios of greatest demand on operator staffing.
These scenarios show how required actions can be performed using the available four operators, with three operators performing local manual operations.
From these scenarios it can be seen that considerable additional time is available where operators are in standby to allow for unanticipated problems.
Additional margin is provided by the availability of the Shift Supervisor, callback personnel from instituting the Emergency Plan, and fire brigade personnel once fire suppression activities are completed, although credit for these additional personnel is not taken within this evaluation.
Attachment to P-86462 Based on the above, it is concluded that four operators can adequately handle the required shutdown functions following a fire, and adequate staffing levels are maintained. Changes will be made to the shutdown procedure to enhance guidance to operators on actions that may be required based on a specific location of the fire.
TABLEI LOCALLY OPERATED EQUIPMENT BY FIRE AREA Fire Area Equipment Croup /
Equipment Location 4/
5 TB (TrainA)
HV-3133-1 -1/
A TB HV-31191 B
TB HV-3 I 33-2 B
TB HV-4221-1 1/
A TB HV-4221-3 T/
A TB HV-4153 D
CT LV-3250-2 B
TB HV-2237 C
TB HV-4221-2 1/
D SW HV-4225 C
TB HV-2238 1/
C TB HV-4226 1 1/
D SW HV-4226-2 T/
D SW HV-22133 -
C TB HV-4257 A
TB HV-2293 I/
C TB PV-22129-I C
TB HV-3220-6 C
TB PV-22153 C
TB fan transfer switches (only for fire in access control boy)
Operate Cire. H O C
TB 2
Makeup Pump, Service Water i
Pump, & Service Water Cooling Tower Fan Transfer Switches (3)
Trip EHC Pumps if B
TB HV-2223 not closed V-42383(I A)
B TB V-42385(IB)
B TB V-42379(I C)
B TB V-4238 l(I D)
B TB V-4214 A
TB V-4229 A
TB V-4236 A
TB V-42390 A
TB V-4234 A
TB l
1 DC-86-71 i
TABLE I LOCALLY OPERATED EQUIPMENT BY FIRE AREA (Continued)
Fire Area Equipment Group /
Equipment Location /
5 4
.TB (Train A cont.)
V-42817 B
TB V-4256 A
TB V-4239 C
TB V-4264 8
TB V-42374 A
TB V-4217 A
TB V-4218 A
TB PI-3134 B
TB TB (Train B)
HV-3119I E
TB HV-31122 F
TB HV-4138-1 G
TB HV-4138-2 G
TB HV-4221-1 E
TB HV-422 I-3 E
TB HV-4133 I/
A CT LV-3250-7 F
TB HV-2237 l/
G TB HV-4221-2 H
SW HV-4225 G
TB HV-2238 G
TB HV-4226-1 I/
H SW HV-4226-2 T/
H SW HV-22134 -
G TB HV-4257 E
TB HV-2292 I/
G TB HV-4I I I T/
H CH PV-221301 G
~
HV-3220-6 G
TB PV-22154 G
TB V-42383(A)
F TB V-42385(IB)
F TB V-4238 I(I D)
F TB V-4214 E
TB V-4229 E
TB V-4236 E
TB V-42390 E
TB V-4234 E
TB V-42817 F
TB V-4256 E
TB DC-86-71 2
TABLEI LOCALLY OPERATED EQUIPMENT BY FIRE AREA (Continued)
Fire Area Equionient Group _/
Equipment Location 4./
5 TB (Train B cont.)
V-4239 G
TB V-4264 F
TB V-42374 E
TB V-4217 E
TB V-4218 E
TB HV-2224 not closed Local Start of diesel G
FP fire pump PI-21536-2 E
TB PI-4112 E
CH PI-4206 F
HV-2291 1/
J RB HV-2290 T/
J RB V-46251 -
I RB V-46349 l
RB V-461633 J
RB HV-2238 I/
L TB HV-2109-I-I RB HV-2109-2 i
RB LV-21130 I/
I RB SV-2109 I
L TB Operate ITB exhaust L
TB fan transfer switches (3)
V-211543 3/
I RB V-211158 3/
K RB V-2111591/
K RB V-21ll42 3/
K RB V-21876 37 K
RB V-21884 7/
K RB V-2l l 141 3/
K RB V-21872 -
K RB V-211160 3/
K RB V-211161 7/
K RB V-211162 7/
K RB V-21 l l44 7/
K RB V-211143 7/
K RB DC-86-7 I 3
TABLEI LOCALLY OPERATED EQUIPMENT BY FIRE AREA (Continued)
Fire Area Equipment Group /
Equipment Location _/
5 4
RB (Train A cont.)
Circulator seal O
HS 6/
manual volves in He Storage Bldg (9)
PI-21247 i
RB PDIS-21173 i
RB PI-21302 i
RB RB (Train B)
HV-229i N
RB HV-2290 N
RB HV-4138-1 P
TB V-46251 M
RB V-46349 M
RB V-461633 M
RB HV-2238 P
TB HV-2110-1 M
RB HV-2110-2 M
RB LV-21130 I/
M RB Sv-2110 M
P TB Connect p rtable M
RB turbine water removal pump V-211545 3/
O RB V-21877 37 O
RB V-21885 7/
O RB V-21II85 3/
O RB V-211I86 7/
O RB V-211177 7/
O RB V-21 l 1767/
O RB V-2I I I877/
O RB V-21873 -
O RB V-2ill89 3/
O RB V-211I90 7/
O RB V-2l I l797/
O RB V-211178 7/
O RB PI-21248 -
M RB PDIS-21174 M
RB PI-21302 M
RB Circulator seal S
HS 6/
manual volves in He Storage Bldg (9)
DC-86-71 4
TABLEI LOCALLY OPERATED EQUIPMENT BY FIRE AREA (Continued)
Fire Area Equipment Group /
Equipment Lccation _/
5 4
SW (Train B)
HV-4221-2 R
SW HV-4226-1 I/
R SW HV-4226-2 T/
R SW All (Train A)
Trip instrument air T
TB compressors Monitor Instrumentation CC and operate controls from control room.
V-211214 X2 RB V-3 t l31 T
TB V-3166 T
TB V-211658 X2 RB V-21867 X2 RB V-31919 U
TB V-31921 T
TB V-32109 T
TB V-3102 T
TB V-32108 T
TB V-31101 T
TB V-22345 U
TB V-5288 U
TB V-5287 U
TB V-5203 U
TB V-32308 U
V-4121 XI CT V-21275 X2 RB V-52174 U
TB V-21754 X2 RB All (Train B)
V-211309 Y
RB l
V-4525 V
TB V-31919 W
TB V-31921 V
TB V-3110I V
TB V-22346 W
RB V-5202 W
TB V-5288 W
TB V-5287 W
TB 1
DC-86-71 5
i
TABLE I LOCALLY OPERATED EQUIPMENT BY FIRE AREA (Continued)
Fire Area Equipment Group /
Equipment Location 4_/
5 All (Train B)
V-32308 W
TB V-32108 V
TB V-4101 V
TB V-4102 V
TB V-4567 V
TB V-211658 Y
RB V-21867 Y
RB V-52179 W
TB V-21755 Y
RB V-21829 Y
RB V-4285 V
TB I/ Spurious volves. Operators generally only need to verify position of these volves; per the guidance of Generic Letter 85-01, only one spurious operation needs to be postulated. Thus, for a given fire area, the operator only needs to verify volve position for these volves, and likely will only have to reposition, at most, one of these volves.
2/ Check instrument to confirm system operation.
3_/ Half of these volves in each train are associated with a circulator static seal, and half are associated with a circulator brake. By the guidance of Generic Letter 85-01 only one spurious operation need be considered. Thus, on operator should check the position of the corresponding solenoid volves for the desired circulator's broke and seal system. If the broke or seal is spuriously applied, the operator should reposition the corresponding manual volves and remove on end cop to vent.
Therefore, only seven manual valve operations and removal of an end cop are required for a single fire.
4/ For equipment located outside the control room that must be operated / observed in the first IY2 hours. (The operator remaining in the control room con monitor instruments in the control room and start /stop equipment as required.)
DC-86-7 I 6
TABLEI LOCALLY OPERATED EQUIPMENT BYFIRE AREA (Continued) 5/ Group:
A, E - North half of TB-grade El.
B, F
- South half of TB-grade El.
C, G - Mezzanine El. of TB and Access Control Bay D, H - Non-TB areas (for fire in TB)
I, M
- At levels I and 2 of RB J, N
- At level 5 of RB K, O - At level 3 of RB L, P
- Non-RB areas (for a fire in RB) 0, S
- Valves for helium circulator seals in HS R
- Valves for fire in area SW T, V
- Grade El. of TB for 'All' fire areas U, W - Mezzanine El. of TB and Access Control Bay for 'All' fire areas XI
- Valves in CT for 'All' fire areas X2, Y - Valves in RB for 'All' fire areas 6/ HS - He Storage Building fire area DC-86-71 7
TABLE 2 MINIMUM REQUIRED OPERATING TIME FOR VARIOUS ACTION GROUPS Minimum Fire Area Train Group Time Required Notes TB A
A 21.5 10 operations & 3 verifications B
19.5 9 operations & I verification C
23 12 operations & 2 verifications D
23.5 2 operations & 3 verifications B
E 24 13 operations & 2 verifications F
19.5 9 operations & I verification G
20.5 9 operations & 3 verifications H
15 2 operations & 4 verifications RB A
I 28 7 operations & 4 verifications J
12 2 verifications K
26 9 operations L
12 I operation & 2 verifications Q
19 9 operations B
M 33 7 operations & 4 verifications N
4 2 operations O
28 9 operations P
12.5 2 operations & I verification S
19 9 operations SW B
R 12 I operation & 2 verifications DC-86-71
-l-
^ ',TABL.E 2 e
MINIMUM IEQUIRED OPERATING TIME FOR VARIOUS ACTION GROUPS
's,/
(continued) m.
S.
Minimum
.,, ~
Fire Area Tidin Group Time Required Notes All A
T 18 8 operations 17 7 operations
,[I,.
XI 12 2 operations X2 20 5 operations B
V 18
~
8 operations W
17 7 operations Y
20
~,',
5 operations
/
d
/
r i
- 4 h
s f
I I
l-l
\\
l DC-86-7 I 2-i
TABLE 3 SHUTDOWN SCENARIO STAFFING Scenario: 1 Fire Location: Turbine Building (Area TB)
Shutdown Method: Train A Operator Tim _ e Period (min.)
Actions 1
0 - on Operate equipment from control room, monitor instrumentation, maintain communications.
2 0 - 10 Respond to assembly location.
10 - 35.5 Perform Group-D actions including 4 volve operations and 3 verifications in areas SW and CT, as well as start of ACM Diesel.
35.5 - 45 Standby to assist as directed by Operator I until access to TB is available.
45 - 66.5 Proceed to Turbine Building for Group-A actions, including 'l0 volve operations and 3 verifications.
66.5 - on Standby to assist as directed by Operator 1.
3 0 - 10 Respond to assembly location.
10 - 30 Proceed to Reactor Building to perform Group-X2 actions, (5 valve operations) 30 - 45 3tandby to assist as directed by Operator i until access to TB is available.
45 - 76 Proceed to Turbine Building to perform Group-C and T actions, including I4 operations, 2 verifications, operating 5 transfer switches, and tripping the instrument air compressors.
76 - on Standby to assist as directed by Operator 1.
DC-86-71 TABLE 3 SHUTDOWN SCENARIO STAFFING (Continued)
Scenario:
1 (cont'd) j Fire Location: Turbine Building (Area TB)
Shutdown Method: Train A Operator Time Period (min.)
Actions 4
0 - 10 Respond to assembly location.
10 - 45 Standby to assist as directed by Operator I, until access to TB is available.
45 - 71.5 Proceed to Turbine Building to perform Groups-B and U actions, including 15 valve operations, I verification, and tripping of the EHC pumps.
71.5 - on Standby to assist as directed by Operator 1.
DC-86-7 I,
TABLE 3 SHUTDOWN SCENARIO STAFFING (Continued)
Scenario: 2 Fire Location: Turbine Building (Area TB)
Shutdown Method: Train B Operator Time Period (min.)
Actions 1
0 - on Operate equipment from control room, monitor instrumentation, maintain communications.
2 0 - 10 Respond to assembly location.
10 - 25 Perform Group-H actions including I volve operation, and 4 verifications.
25 - 45 Standby to assist as directed by Operator 1, until access to TB is available.
45 - 77 Proceed to Turbine Building to perform Groups-E and V octions, including 21 valve operations and 2 verifications.
77 - on Standby to assist as directed by Operator I.
3 0 - 10 Respond to assembly location.
10 - 30 Proceed to the Reactor Building to perform Group-Y actions (5 valve operations).
30 - 45 Standby to assist as directed by Operator I, until access to TB is available.
t 45 - 71.5 Proceed to the Turbine Building to perform Groups-F and W
- actions, including 15 volve operations, I
l verification, and tripping of the EHC pumps.
71.5 - on Standby to assist as directed by Operator l.
l l
l l
DC-86-71.-.
TABLE 3 SHUTDOWN SCENARIO STAFFING (Continued)
Scenario: 2 (cont'd)
Fire Location: Turbine Building (Area TB)
Shutdown Method: Train B Operator Time Period (min.)
Actions 4
0 - 10 Respond to assembly location.
10 - 45 Standby to assist as directed by Operator I, until access to TB is available.
45 - 60.5 Proceed to the Turbine Building to perform Group-G actions including 9 valve operations and 3 verifications.
60.5 - 73 Local start of diesel fire pump.
73 - on Standby to assist as directed by Operator I.
)
t DC-86-7 I -.
TABLE 3 SHUTDOWN SCENARIO STAFFING (Continued)
Scenario: 3 Fire Location: Reactor Building (RB)
Shutdown Method: Train A Operator Time Period (min.)
Actions 1
0 - on Operate equipment from control room, monitor instrumentation, maintain communications.
2 0 - 10 Respond to assembly location.
10 - 28 Proceed to the Turbine Building to perform Group-T actions, including 7 volve operations and tripping the instrument air compressors.
28 - 45 Standby to assist as directed by Operator 1, until access to RB is available.
45 - 75 Proceed to Reactor Building levels I and 2 for Group-l actions, including 7 volve operations and 4 verifications, and level 5 for Group-J actions (2 verifications).
75 - on Standby to assist as directed by Operator I.
3 0 - 10 Respond to assembly location.
10 - 29 Proceed to Turbine Building for Group-L and U
- actions, including 7 valve operations, 3 transfer switches, and 2 verifications.
29 - 45 Standby to assist as directed by Operator I, until access to RB is available.
45 - 73 Proceed to Reactor Building to perform Group-K actions, including 8 valve actions and removal of a vent cap to release the circulator seal / brake if spuriously applied.
l l
DC-86-71..
-e
-m--
e,-
,,--mar,-,
y TABLE 3 SHUTDOWN SCENARIO STAFFING (Continued)
Scenario: 3 (cont'd)
Fire Location: Reactor Building (RB)
Shutdown Method: Train A Czerator Time Period (min.)
Actions 3 (cont'd) 73 - on Standby to assist as directed by Operator 1.
4 0 - 10 Respc.nd to assembly location.
10 - 29 Perform Group-O circulator seal valve operations in He Storage Building.
29 - 41 Proceed to cooling tower valve pit (area CT) to perform Group-XI actions (2 valve operations).
41 - 45 Standby to assist as directed by Operator I, until access to RB is available.
45 - 65 Proceed to the Reactor Building to perform the Grou;;-X2 actions (5 volve operations.)
65-on Standby to assist as directed by Operator 1 DC-86-7 l TABLE 3 SHUTDOWN SCENARIO STAFFING (Continued)
Scenario: 4 Fire Location: Reactor Building Shutdown Method: Train B Operator Time Period (min.)
Actions 1
0 - on Operate equipment from control room, monitor instrumentation, maintain communications.
2 0 - 10 Respond to assembly location.
10 - 29.5 Proceed to Turbine Building to perform Group-P and W
cetions (9
volve operations and I verification).
29.5 - 45 Standby to assist as directed by Operator 1, until access to RB is available.
45 - 82 Proceed to the Reactor Building to perform Group-M and N actions (8 valve actions, I verification) and connect the portable turbine water removal pump; assisted by Operator 4. (Note - turbine water removal pump not immediately required.)
82 - on Standby to assist as directed by Operator 1.
3 0 - 10 Respond to assembly location.
10 - 28 Proceed to Turbine Building to perform Group-V actions (8 valve operations).
28 - 45 Standby to assist as directed by Operator I, until access to RB is available.
45 - 73 Proceed to Reactor Building to perform Group-O actions, including 8 valve operations and removal of a vent cap to release the circulator seal / broke if spuriously applied.
DC-86-7 I TABLE 3 SHUTDOWN SCENARIO 5TAFFING (Continued)
Scenario: 4 (cont'd)
Fire Location: Reactor Building Shutdown Method: Train B Operator Time Period (min.)
Actions 3 (cont'd) 73 - on Standby to assist as dirceted by Operator I.
4 0 - 10 Respond to assembly location.
10 - 29 Perform Group-S circulator seal valve operations in He Storage Building.
29 - 45 Standby to assist as directed by Operator I, until access to RB is available.
45 - 65 Proceed to Reactor Building to perform Group-Y actions (5 valve operations).
65 - 82 Assist Operator 2 in connection of portable turbine water removal pump.
82 - on Standby to assist as directed by Operator I.
DC-86-71.
TABLE 3 SHUTDOWN SCENARIO STAFFING (Continued)
Scenario: 5 Fire Location: Service Water Pump House (SW)
Shutdown Method: Train B Operator Time Period (min.)
Actions 1
0 - en Operate equipment from control room, monitor instrumentation, maintain communication.
2 0 - 10 Respond to assembly location.
10 - 28 Proceed to Turbine Building to perform Group-V actions (8 valve operations).
28 - 45 Standby to assist as directed by Operator I, until SW is accessible.
45 - 57 Proceed to area SW to perform Group-R actions (1 valve operation and 2 verifications).
57 - on Standby to assist as directed by. Operator 1.
3 0 - 10 Respond to assembly location.
10 - 27 Proceed to the Turbine Building to perform Group-W actions (7
volve operations.)
27 - on Standby to assist as directed by Operator I.
4 0 - 10 Respond to assembly location.
10 - 30 Proceed to the Reactor Building to perform Group-Y actions (5 valve operations.)
30 - on Standby to assist as directed by Operator I.
DC-86-71 :
s e
)
REACTOR BUILDING (RB)
CONTROL TURBIT COMPLEX LUBE OIL (CC)
STORACE ROOM (T9
~
BLDC.10 U)
TURBINE I
TeRB,m BU,_
(TB) i I
AUX.
BOILER DIESEL (AB)
GEERATORS y STORACE (DA) (DB) ne I
I FIGURE 2.1 INTERIOR FIRE AREAS GRADE ELEVATION Rev. 3
O CIRCULATING % t TER j
MAKE-UP PUMP BUILDING (CW) l
$.- a Y
$U OO F
FIRE PUMP SERVICE WATER BUILDING BUILDING (SW)
(FP)
AND COOLING TOWER ($T)
CIRCULATING WATER PUMP HOUSE & BASIN (Ct1
'.h REACTOR BUILDING (RB)
F BULDING l0 L _
(T)
TURBirE BulLDING ACM CONTROL N
BUILDING (AC)
EVAPORATING COOLING BUILDING (EB)
ACM DfESEL (AD) i FIGURE 2.2 EXTERIOR FIRE AREAS GRADE ELEVATION Rev. 3
(.
p-g.
p-Distribution:
Central File Stavaniugh NRR 11;'.
CMEB Reading
(
APR ? 01992 HDenton ECase RVo11mer RMattson Mr. 5. A. Bernsen 5Hanauer Manager of Nuclear Engineering WJohnston
~
Sechtel power Corporation LRubenstein p.0. Box 3g65 OParr San Francisco, CA 9411g VPanciera VBenaroya
Dear Mr. Bernsen:
RFerguson LMiller In response to your letter of March 9. Ig82, the staff has given further consideration to the issues you have raised regarding potential control room fires and the appropriate methods for providing protection from the
. effects of such fires.
You met with members of the NRC staff on July 2g.
1981. to have an interchange of ideas regarding fire protection for the control room. The major agenda item was the proposed control room fire protection criteria contained in your letter of July 2. Ig81. During the course of the meeting, you expressed certain concerns regarding our approach to fire protection in the control room and asked us to address f-
. certain questions you had regarding the likelihood and consequences of Q
control room fires. Since then, we have evaluated the control room fire issue on a number of plants in the operating license review process and have met on several occasions with an industry group seeking fire protec-tion requirements including the clarification of control room fire protection issue.
Before responding to your specific questions. I think it would be better to discuss what I perceive to be your major concern with the approach the staff has taken regarding exposure fires in the control room and the usually assumed need for electrical isolation between the control room and the remote %
shutdown station.
I understand that you have no reservations with regard ts" providing a remote shutdown station which can be electrically isolated from the main control board in the contml room. Thus. in the event of a fire which damages the main control board, the remote shutdown station is capable of accomplishing those plant shutdown functions provided by the main control board independent of the control room.
Your concern with isolating the remote shutdown station, as I understand it is that panels in the control room complex that automatically control plant shutdown operations after scram initiation should not be transferred to the remote shutdown panel, and isolated from the control room. The transfor could result in interrupting an automatic protective action at a critical time and the switchlag or isolation devices could introduce greater unreliability into the circuitry. We appreciate your concern. However, we cannot accept your postulattoa that an exposure fire in the vicinity of these panels without additional protection will not damage adjacent panels which provide redundant automatic shutdown logic.
5$5 1$
l0-
C' t..................................../....................
" ' T.......................
==>
]~
r r- ~
s g*
g h
g g'
y.-
d Mr. 5. A. Bernsen o We feel that Appendix R to 10 CFR part 50 provides a solution to your Appendix R states the technical requirements for separation.
concern.
These requirements provide that one train of systems necessary to achieve and maintain hot shutdown conditions from either the control room or l
emergency station (s) is free of fire damage.
paragraph III.G.2 specifically addresses the concern regarding maloperation of redundant shutdown systems and specifies means which should be implemented to meet the " free of fire damage" requirement, namely:
1.
separation by three hour barriers; l
separation by 20-foot horizontal distance; or 2.
3.
provisions for fire barriers having a one-hour rating and automatic fire suppression in the area under consideration.
If these three means of providing assurance of availability of one train of rhutdown equipment are not adequate, then alternative shutdown capability j
independent of the cables, systems or components in the area is specified.
If you find the provision of alternative shutdown for these logic functions objectionable (i.e., switches for transfer of controls to a remote shutdown j
station), a nober of options listed above could be employed to protect the -
function, such as a one-hour fire barrier with a suppression system.
Accordingly, wr suggest that you modify your control room criteria to consider l
the effects of exposure fires on redundant control panels required for hot shutdown, and Irovide adequate separation to meet tto technical requirements F
of Appendix R to 10 CFR part 50.
At the and of our meeting on July 23 you requested that we respond to three l
questions. These questions and the staff's response are as follows:
What fires have occurred in the control rooms of nuclear 4
Question 1:
power plants?
A fire which has required the evacuation of the control room
Response
has not yet occurred. Between January Ig55 and May 1978, two cabinet fires have been reported in control rooms.
Enclosed is a list of references on fire incidents inforination on two control room fires, supplied to us by American Nuclear Insurers, and a reprint from Nuclear Safety entitled " Nuclear
[
plant Fire Incident Data File."
Ouestion 2:
When can operators return to the control room after a firef The operators could return to the control room when the
Response
following conditions have been met:
1.
The fire has been extinguished and so verified by appropriate fire 3rotection personnel.
2.
The control room tas been deemed habitable by appropriate
'4&protee44 cn-pe rsonnel-and-the-s hi ft-s u pe rv i s o rr--
)
- * * >..........j........
j
.ns) j 1
j..........
s
- p.. -
p.,-
g
%m.w>.
/
g.. -
c e,
Mr. 5. A. Bernsen Damage has been assessed and, if necessary, corrective action has been taken to assure necessary safety, 3.
control and information systems are functional (some operators may assist with these tasks) and the control room.
Turnover procedures which assure an orderly transfer of control from the alternate shutdown panel to the 4.
control room has been completed.
We consider that it would take at least one hour to accomplish the above tasks.
What action can they taket
_0uestion 1:
Operators returning to the control room can take any actions Controls compatible with the condition of the control room.
Resoonse:
in any area (cabinet) where the fire occurred wou
~
before controls in such cabinets are available.
Con-trols in undamaged area (cabinets) could be operated as Hinor modifications inside the control room say required.
(.9 be performed to reach cold shutdown.
With respect to your comments on recent requirements to address 3
fa actuations or operations caused by a control roo to discuss these instances in more detail.
I hope this letter and staff comments are responsive to your concern Mr. Vollmer will send you the results of our discussions with the fire protection group when they are available.
Sincerely.
Oristad signed by
,, E.R.5estes Harold R. Dentone Director Office of Nuclear Reactor Regulation l
Enclosures:
(3) As stated Concurrences by D5I & DE on technical discussion on NOTE:
nest concurrence sheet.
W
- i..Ds 4
..... *!lys e.........
.:.mna................................
..E
.= Dent.............................
-> av. =r.o.
4 'Y 82.... m./
../. 8. 2.....4../......../.8.2.......................................................
4 i
... A.../....
ses r. net n r nsev
==>
omr-Ai
&rmrono,
. cmes.e
l 1
control boy portion adjacent to the south side of the Reactor Building. Like the Reactor Building, the Turbine Building is constructed with insulated dual O-corrugated steel walls and a Class A metal deck type roof.
Its physical configuration, oiso similar to the Reactor Building, is on open structure design consisting of open steel floor grating, open stairways and, except as noted below, contains unsegregated machinery areas. The normal ventilation systems provide for removal of smoke and other airborne products of combustion during and after a fire.
The Turbine Building return fans move air out of the building, but normally recirculate a portion of it to conserve internal heat. The Turbine Building ventilation systems are modified to permit manual operation of the exhaust air dampers for smoke removal.
Major fire hazards within the Turbine Butiding space are either segregated by 3-hour fire rated enclosures, protected by an automatic fire suppression system, or both. These are as follows:
1.
Diesel Generator Rooms 2.
Auxiliary Boiler Room p
3.
Turbine Lube Oil Room b
4.
Turbine Lube Oil Storage Room 5.
Hydrogen Storage Room 6.
Three Room Control Complex 7.
Hydrogen seal oil unit 8.
Congested cable area at the "C" wall items I through 5 are separate fire areas that are (or will be following modifications described in Section (4.0) bounded by fire rated walls. Exemption Request 3.1 oddresses the three room Control Complex fire walls. Also, fire suppression systems are provided for areas I, 3, 4, and 5.
Items 5, 7, and 8, although not enclosed within a fire rated boundary, have been protected by a fire suppression system designed for the specific fire hazard involved. The turbine electro-hydraulic control unit uses "Fryequel" fire-resistant hydraulic fluid, and has local fire-hose stations and CO2 hose reel.
The balance of the Turbine Building fire hazards consist of cable trays and transient fire hazards dispersed throughout the building.
O DC-85-04 3-7 Rev. 2 (d/86)